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Create batches in linq
... int maxItems)
{
return items.Select((item, inx) => new { item, inx })
.GroupBy(x => x.inx / maxItems)
.Select(g => g.Select(x => x.item));
}
}
and the usage would be:
List<int> list = new L...
How to sort the result from string_agg()
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With postgres 9.0+ you can write:
select string_agg(product,' | ' order by product) from "tblproducts"
Details here.
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What's the difference between streams and datagrams in network programming?
...ets
stream (TCP, order and delivery guaranteed,no duplication,no length or char boundaries for data,connection-oriented,reliable, concurrency)
datagram(UDP,packet-based, connectionless, datagram size limit, data can be lost or duplicated, order not guaranteed,not reliable)
raw (direct access to lowe...
Escaping keyword-like column names in Postgres
...). A delimited identifier is always an
identifier, never a key word. So "select" could be used to refer to a
column or table named "select", whereas an unquoted select would be
taken as a key word and would therefore provoke a parse error when
used where a table or column name is expected.
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How can I make a ComboBox non-editable in .NET?
I want to have a "select-only" ComboBox that provides a list of items for the user to select from. Typing should be disabled in the text portion of the ComboBox control.
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How to delete a workspace in Perforce (using p4v)?
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From the "View" menu, select "Workspaces". You'll see all of the workspaces you've created. Select the workspaces you want to delete and click "Edit" -> "Delete Workspace", or right-click and select "Delete Workspace". If the workspace is "lock...
Why is there “data” and “newtype” in Haskell? [duplicate]
...rcher | Accountant
data Race = Human | Elf | Orc | Goblin
data PlayerCharacter = PlayerCharacter Race Profession
When using newtype, you're restricted to just one constructor with one
field.
Now consider the following type:
data CoolBool = CoolBool { getCoolBool :: Bool }
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Remove duplicates in the list using linq
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var distinctItems = items.GroupBy(x => x.Id).Select(y => y.First());
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Rails filtering array of objects by attribute value
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Try :
This is fine :
@logos = @attachments.select { |attachment| attachment.file_type == 'logo' }
@images = @attachments.select { |attachment| attachment.file_type == 'image' }
but for performance wise you don't need to iterate @attachments twice :
@logos , @images...
How to play with Control.Monad.Writer in haskell?
...ype of logNumber is logNumber :: (Show a, Monad m) => a -> WriterT [[Char]] m a for me.
– kmikael
May 27 '15 at 20:15
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